| 3R Design Ltd | Manufacturing | 2015 |
| A & G Repairs Limited | Wholesale & retail | 2023 |
| A & L Williams Limited | Construction | 2020 |
| A & M Williams Plumbing & Heating Limited | Construction | 2024 |
| A Hughes-Jones, Dyson & Co Ltd | Professional & scientific | 2025 |
| A L I Building Design Limited | Professional & scientific | 2004 |
| A-Pedwar Cyfyngedig | Professional & scientific | 2008 |
| AB Enterprise Consulting Ltd | Information & communication | 2018 |
| Aberglaslyn Hall Limited | Hospitality | 2016 |
| Abseil Services Limited | Construction | 2023 |
| Accordia Accounting Limited | Professional & scientific | 2021 |
| Activexsport Ltd | Wholesale & retail | 2025 |
| Acwaterra Ltd. | Professional & scientific | 2022 |
| Adar Gleision CYF | Real estate | 2018 |
| Addewid CYF | Administrative & support | 2025 |
| Adeiladau Ansawdd Arbennig CYF | Construction | 2024 |
| Adeiladwaith Ebeneser CYF | Manufacturing | 2019 |
| Adeiladwaith HP Construction CYF | Professional & scientific | 2025 |
| Adeiladwyr D & S Jones Builders Ltd | Construction | 2006 |
| Adra (Cymru) CYF | Wholesale & retail | 2007 |
| Adra Lodge CYF | Hospitality | 2016 |
| Aelwyd - Datblygwyr Eiddo/Property Developers Ltd | Real estate | 2024 |
| Afon Goch Children's Homes Ltd | Health & social care | 2002 |
| AGE Cymru Gogledd Masnachol CYF | Hospitality | 2013 |
| AGE Cymru Gwynedd a MON | Health & social care | 2011 |
| AGE Cymru North Trading Ltd | Health & social care | 2013 |
| Agnostic Adviser Limited | Professional & scientific | 2025 |
| Aiden Barber Saloon Ltd | Other services | 2026 |
| Ainsworth's Fish & Chips Limited | Hospitality | 2023 |
| Airworld Aviation Museum Limited | Arts & recreation | 2010 |
| ALA Self Storage Ltd | Transport & logistics | 2025 |
| Alan a Pollard Consultancy Limited | Information & communication | 2017 |
| Alan Williams Coaching Ltd | Education | 2015 |
| Alice Elizabeth Snape Ltd | Hospitality | 2024 |
| Almar Consultancy Ltd | Professional & scientific | 2013 |
| ALS Housing Services Limited | Real estate | 2023 |
| Altra Glass Limited | Other services | 2020 |
| Altra Trade Frames Limited | Wholesale & retail | 2022 |
| Alwyn Thomas Tractors Limited | Wholesale & retail | 2021 |
| AM Stori CYF | Information & communication | 2019 |
| Amdro Limited | Manufacturing | 2004 |
| Amser I Siarad Ltd | Other services | 2003 |
| AND NOW Limited | Agriculture & fishing | 2013 |
| Angela Evans Jewellery Ltd | Manufacturing | 2024 |
| Anglesey & Gwynedd Groundworks Ltd | Construction | 2019 |
| Anglesey Arms Limited | Hospitality | 2013 |
| Anglesey Auto Tint Ltd | Wholesale & retail | 2020 |
| Apex Technical Training Limited | Extraterritorial | 2019 |
| ARB Giant Ltd | Agriculture & fishing | 2024 |
| Ardudwy Travel Ltd | Hospitality | 2017 |
| Areli Holdings Ltd | Professional & scientific | 2013 |
| Arete Outdoor Centre | Education | 2014 |
| Arfon Software Ltd. | Information & communication | 2000 |
| Argol CYF | Information & communication | 2018 |
| Argraffwyr Gwynedd (Printers) Cyfyngedig | Manufacturing | 1979 |
| Aria Studios CYF | Information & communication | 2021 |
| Ariandy Limited | Extraterritorial | 2013 |
| Arthur Salisbury Holdings Limited | Professional & scientific | 2011 |
| Arthur Salisbury Limited | Real estate | 1953 |
| ASH & Roots Ltd | Agriculture & fishing | 2024 |
| Asiant CYF | Professional & scientific | 2023 |
| Astral Dynamics CYF | Information & communication | 2011 |
| Aton Solar CYF | Construction | 2011 |
| Auxilium Catering Ltd | Hospitality | 2025 |
| Awen Media Ltd | Information & communication | 2013 |
| Awenydd CYF | Arts & recreation | 2003 |
| Axis Precision Limited | Manufacturing | 2001 |
| Axis Therapy Ltd | Arts & recreation | 2010 |
| B & K Williams Limited | Wholesale & retail | 2005 |
| B P Bar Ltd | Hospitality | 2026 |
| Baby First Ltd | Wholesale & retail | 2010 |
| BAD Fairies Ltd | Information & communication | 2016 |
| Bandbroad Ltd | Professional & scientific | 2014 |
| Barnet Pepper Holdings Limited | Financial services | 2023 |
| BEA Italia CYF | Wholesale & retail | 2020 |
| Beacon Climbing Centre Limited | Arts & recreation | 2002 |
| Beaucari Access & Rigging Ltd | Construction | 2023 |
| Beautiful Snowdonia Limited | Hospitality | 2020 |
| Becws Melyn CYF | Hospitality | 2023 |
| Beddgelert Woodcraft Limited | Wholesale & retail | 2022 |
| Bedwyr Jones A'I Gwmni CYF | Agriculture & fishing | 2021 |
| BEE Brothers Construction Ltd | Construction | 2024 |
| BEE Robotics Limited | Manufacturing | 1999 |
| Beeshaw Ltd | Hospitality | 2026 |
| Bennel Electrical Ltd | Construction | 2026 |
| Berfa Garden Services Ltd | Administrative & support | 2021 |
| Berts London Ltd | Wholesale & retail | 2026 |
| Bethel Plant Sales Limited | Wholesale & retail | 2019 |
| Bethel Training Company Ltd | Professional & scientific | 2021 |
| Bhojon Bilash Ltd | Hospitality | 2026 |
| Binshare Ltd | Information & communication | 2025 |
| Black BOY (Caernarfon) Limited | Hospitality | 1998 |
| Blades 22 Ltd | Other services | 2025 |
| Blawd CYF | Hospitality | 2012 |
| Bocs Projects Limited | Construction | 2022 |
| Bosworth Leisure Group Ltd | Hospitality | 2025 |
| Bosworth Leisure Ltd | Hospitality | 2021 |
| Bowldro Ltd | Arts & recreation | 2023 |
| Braf Dinas Dinlle CYF | Hospitality | 2021 |
| Brandcrest Limited | Other services | 2023 |